Monte Carlo method procedure for evaluations of the lightning performance of transmission lines based on the concepts of critical and anti-critical currents

Abstract:
This work proposes a calculation procedure of the Monte Carlo method applied for assessing the lightning performance of transmission lines (TLs) based on the traditional and well-known concept of critical current, defined as the minimum lightning peak current that leads TLs insulators to flashover, and in the novel concept here presented and designated as the anti-critical current, considered as the maximum lightning peak current that does not lead TLs insulators to flashover. The proposed procedure provided a significant reduction of the number of ATP simulations demanded by the Monte Carlo method since it just calls the ATP simulation if the following condition is achieved: Ianti-CΩ to 80 Ω. Additionally, the proposed procedure allows Monte Carlo simulations with more rounds, providing lower errors of lightning peak current distribution and of backflashover probability, and the decrease of the dispersion coefficient, ensuring consistent results with low computational burden.